Autotile doesn't work with edge-based tiles?

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:bust_in_silhouette: Asked By godutmaster

Let’s say that this is my tileset.
my 32x32 tileset
It consists of 24 32x32 tiles. I always want the red square to appear whenever i use the tiles. if the floor would not fit the whole square, it can always draw half of it. I also want to make it autotile, since i won’t place them all manually. The problem is, whenever i try to make the autotile, the tiles just wont place correctly. How should i set my bitmask?

How tiles align:


How tiles should align:

:bust_in_silhouette: Reply From: Hargbratch

I am not an expert but I’ve played around quite a bit with the autotile tool.

enter image description here
enter image description here
to set the bitmask for this specific tileset:
set tilesize in the inspector to 3x3 (i forget the name of what you actually click)
then click inside the peach areas.

obviously to get what you are shooting for you’ll need to adjust to your own needs

I expect you will need more tiles, the set above uses 55

I’m not very strong in the math/logic of all this, getting to this number was all trial and error, it’s possible/probable that I didn’t do this optimally.

edits:
I had to mess around to figure out how to put images in a post.

The reason for the apparent duplication of the top right’s block of four tiles is so I could have inside and outside corners.